Hydrologic and topographic gradient effects on woody vegetation of tree islands in the Everglades Wildlife Management Area

Water management in the Everglades has been a challenge for managing agencies for quite some time. Presently, restoration efforts are underway to reestablish natural hydrological patterns such as flow, depth, and hydroperiod. Tree island health is of particular concern because of its importance to the functional integrity of the greater Everglades ecosystem. This study was designed to determine the effects of different hydrological patterns and elevations on native woody vegetation on tree islands. The study site was the Everglades Wildlife Management Area (EWMA) in the north central Everglades. The study site was broken up into two hydrological zones: dry zone and moderately wet zone. It was found that both hydrology and relative elevation were important predictors of woody species diversity and density. Average hydroperiod and ponding depth were the best sole predictors explaining up to 50% of the woody vegetation variability found within the tail and fringe community as well as the whole tree island.